NTT DoCoMo on Thursday said it planned to use Google Internet search and other services in mobile phones, giving Google a major platform for delivering services and ads to the Japanese.

The companies said in a joint statement that Google search results would appear by default via the search portal available on DoCoMo i-mode handsets. In addition, keyword-based ads from Google's AdWords advertising platform would also appear with results. The search and advertising services will be deployed in the spring.

Tokyo-based DoCoMo was in discussions with Google to pre-install Google Maps for Mobile on handsets. The companies were also working on adding other Google services, such as e-mail, YouTube video, and the ability to share and publish photos over the Web. In addition, Google would be set as the default start page on upcoming DoCoMo handsets with full-browser capabilities.

DoCoMo was also considering offering handsets with Google's Android mobile software platform, which is expected to ship in the second half of the year.

DoCoMo has more than 51 million subscribers in Japan, which is more than half the number of mobile phone subscribers in the country. The company claims that 48 million of its customers access the Internet with their phones.

Nevertheless, DoCoMo is battling fiercely to hold and gain subscribers. Its major rivals in Japan include KDDI and Softbank. Google is the world's largest search engine, but in Japan it's behind Yahoo Japan, which has 65% of the Japanese search market. Japan has more than 100 million people with mobile phones.